Adjustable stroke tube bending tool



July 23, 1957, A. P. ANELLO 2,800,161

ADJUSTABLE STROKE TUBE BENDTNE Toor,

original Filed July 15.1949

53 Em: gig/7T United States Patent O 2,800,161 ADJUSTABLE STROKE TUBE BENDING TOOL Anthony P. Anello, Tampa, Fla. substituted for abandoned application Serial No. 104,890,

July 15, 1949. This application September 24, 1956 Serial No. 611,789

4 Claims. (Cl. 153-33) movement of which may be regulated so that any ac.

cidental denting of a tube being bent is prevented.

A further object of the invention is to provide a bending tool of the character indicated above comprising an exchangeable bending die and a plurality'of exchangeable tube holding dies. Y

An additional object of the invention is to provide a bending tool of the charatcer indicatedk above wherein the distance between the bending die and the holding dies can be adjusted toibend a tube to a predetermined.

angle.

The invention consists in the details of construction and in the combination and arrangement of the several partsv of my improved tube bending tool whereby certain advantages are attained, aswill be hereinafter more fully set forth.

In order that my invention may be better understood, I will now proceed to describe the same with reference to the accompanying drawing, wherein:

Figure 1 is a view in perspectiveiof an embodiment of a tube bender in accordance with the invention;

Figure 2 is a view in section, taken on theiline 2--2 of Figure 1; l Y

Figure 3 is a left end elevation of'Figure 2;

Figure 4 is a partial view of a modified form of the tube bender in accordance with the. invention partly shown in top plan and partly in section;

Figure 5 is a View in section,taken.on the line 5-5 of Figure 4;

Figure 6 is a view in perspective of an equalizer arm used in the modified form of the tube bender shown in Figure 4; and

Figure 7 is a detail view of an adjusting unit adapted to be secured pivotally on the adjusting levers of the tube bender.

The tube bender as embodied in this invention comprises a frame F having two longitudinal side members 10 preferably made from hat iron. The side members are arranged to rest on their edges on the iloor, work bench or the like and a cross member 11 also preferably made from fiat iron is welded with its ends to the side member 10 intermediate their ends, as at 12, so that the main portions of the side members 10 run parallel to each other.

One end portion of each side member 10, hereinafter called the front end portion 13, is bent at an obtuse angle to the main portion of the side member so that the two portions 13 extend inwardly toward each other.

2,800,161 Patented: July 23, 1957 The front tip end portion 14 of each portion 13 is bent t', lee t v forwardly `to run parallel to the main portions of the side members 10 and is curved upwardly.

A main pivot pin 15 extends through the two tip end portions14and a rectangular plate 16 is welded or otherwise secured on the adjacent parts of the side members v i 10 and the front portions 13 thereof.

The two adjusting plates 17 are pivotally rnounted intermediate their ends on the-main pivot pin adjacent to the' inner surfaces ofthe front-tip end portions 14. i

j An adjusting nut` 18 has a pair of stub axles`19 extending, diametrically in opposite directions from the nut which is oscillatingly supported by said stub axles betweenV the lower` end portions ofthe adjustment plates justing plates 17 adjacent to the upper edges of said plates andthe main pivot pin 15 and the upper pivot pin 20V are preferably disposed on the longitudinal center lines of the adjusting plates 17.

An adjusting ,rod 21 is provided on4 its front end por? tionV with a thread 22 adapted to engage the nut 18. The

rear eiid` portion of the rod 21 extends through hole 23' provided in the cross member 11 and is prevented from sliding rearwardly through said hole by a shoulder` ring.

24 secured on they adjusting'y rod in front of the cross member 11. Y

A stub shaft 25 is rotatably supported" by a bearing 26 secured by a" bracket plate 27 to theunder side of. the plate 16 soV that the bearing is disposed centrally between the side members 10and extends rearwardly and upwardly in relation to the plate 16. The lower or forward end portion of the stub shaft 25 is connected with the rear end portion of the adjusting rod 21 by means of a univer' sal joint 28 aii'd a hand wheel 29 or the like is mounted on theupper or rear end portion of the stub shaft 25'.,`

By rotating the hand Wheel 29, the adjusting plate 17 is pivoted in clockwise or counter-clockwise direction about-the main pivot pin 15 and a stop pin 30 or the like i'sA arranged to extend through the adjusting rod 21 adjacent to the front end of saidrod to prevent an accidentalremoval of the nut 18 from the threaded portion227 of the rod 21.

One end, hereinafter called the front end, of a sleevelikeimember 31 is partly closed by a plate 32 welded orv otherwise secured to-the sleeve-like member and a pair of longitudinal lflanges 33 are Welded onto this member adjacent toits front end and run parallel to each other. The ilangesare spaced from each other so that they canenter between the upper end portions of the adjusting-plates 17, Wherethey are pivotally mounted on the '-upper pivot pin 20, which extends` through the anges 33' adjacent to their front edges.

round -postl` extends through the plate ladjaceiit'l each of the rear corners of said plate and is welded or otherwise secured to the adjacent side member 10 and the cross member 11.

On each post 34 a holding or supporting die 35 is pivotally moun'ted and rests on the plate 16. Accidental removal of the die is prevented by a cotter pin 36. The front surface of each die 35 is hollowed out transversely to form a groove 35a having a semi-circular cross seetion of a radius equal to the outside radius of a tube to be bent. The dies 35 are easily exchangeable by simply removing the cotter pins 36.

One end portion of a push bar 37 is pivotally mounted on a pivot pin 38 extending through the flanges 33 adjacent to the rear edges and is disposed between said flanges. On the other or rear end portion of the push bar 37 a bending die 39 is removably and exchangeably mounted and is secured against accidental removal by a pin 40 or the like. The bending die 39 has a hol- An upper pivot pin20" extends through the twoad-r` low neck 41 receiving the rear endportion of the push bar 37 and a die head 42 having a recess 43 in the rear surface thereof. The recess in the die head 42 extends transversely and has a semi-circular cross section of the same radius as the grooves 35a in the holding dies 35. The entire rear surface of the bending die head Vis curved transversely on an arc of the number degrees to Vwhich a tube is to be bent. The bending die restsslidably on the plate 16. j

A handle 44 is removably inserted in the sleeve-like member 31.

When a tube 45 (shown in broken lines in Figure 1) is to be bent, holding dies 35 of the requisite size are mounted on the posts 34 and a corresponding bending die 39 is secured to the push bar 37. The tube is placed transversely against the front surfaces of the holding dies 35 and the handle 44 is swung downwardly in rearward direction forcing the bending die against the tube and bending it. By rotating the hand wheel 29, the upper portion of the adjusting plates 17 are moved forwardly or rearwardly in order to adjust the working stroke of the bending die 39 in relation to the holding dies 35, which will swivel about the posts 34 when the bending die acts on the tube 45.

In Figures 4, and 6, a slightly modied form of a tube bender in accordance with the invention is shown. This embodiment of the invention comprises the same parts as described above with the exception of the holding dies 35, which are replaced by a pair of double dies D, each of which comprises an equalizer arm A and two holding dies H.

Each equalizer arm A has an elongated lever arm 46 provided on its under side with centrally disposed boss 47. A hole 48 extends through the leverarm 46 and the boss 47 and adjacent to each end of the lever arm 46 a hole 49 is provided in said lever arm. The holes 49 are located equidistantly from the hole 48. v

Each holding die H has a transverse groove 50 extending across its front surface and of semi-circular cross section similar to the groove 35a in the holding die 35. In the rear portion of each holding die H a transverse slot 51 is arranged adapted to receive one of the end portions of one of the lever arms 46. Bores 52 and 53, respectively, extend through the upper and lower rear parts of the die H so that the hole 49 and the bores 52 and 53 can be disposed coaxially when the lever arm 46 is located in the slot 51. A headed pivot pin 54 is inserted from below through the bore 53, the hole 49 and the bore 52 and a cotter pin 55 or the like prevents accidental removal of the pivot pin 54. In this manner, the holding dies H are pivotally connected with the equalizer arms A, which in turn are pivotally mounted on the post 34 extending through the central hole 48. A cotter pin 36 prevents accidental removal of the equalzer arm A from theV post 34.

The function of the double dies D is particularly the same as the function of the holding dies 35, but each i double die D affords a longer and a more flexible abutting surface for the tube 45 than the holding die 35.

From the foregoing description, it is thought to be obvious that a tube bending tool constructed in accordance with my invention is particularly well adapted for use by reason of the convenience and facility with which it may be assembled and operated.

What I claim is:

1. In a tube bender of the character stated including a base having two holding dies thereon; a pair of elongate adjusting members, pivot means supporting said members on the base in spaced relation to said dies, said members being vertically supported for rocking movement on an axis extending transversely of the base, a bending die slidably supported on the base for movement relative to the holding dies in a path perpendicular to said axis, a lever pivotally supported at one end between said adjusting members'above the pivot means for swinging movement in a plane parallel to said'path, a push bar pivoted at one end to said bending die, a pivot coupling between the other end of said bar and said one end of the lever at a point between the pivot support for the lever and the bending die and means operatively coupled with said adjusting members for rocking the members on said axis and for holding the adjusting members in their adjusted positions.

2. The invention as set forth in claim 1, wherein the means for rocking and for holdingthe members in adjusted position comprises a shaft, means supporting the shaft on the base for rotary movement and holding the shaft against axial movement, means for effecting rotation of the shaft, and an operative coupling between the shaft and said adjusting members whereby rotary motion of the shaft imparts rocking movement to the adjusting members.

3. The invention as set forth in claim 1, wherein said means for rocking and for holding the members in adjusted position comprises a shaft, means supporting the shaft on said base below said holding dies for rotational movement, the shaft being held against axial movement, a threaded nut positioned between said adjusting members beneath the pivot means therefor, means connecting opposite sides of the nut with the adjusting members for rocking movement on an axis paralleling the lirst axis, said shaft having a threaded end threaded through said nut whereby rotation of the shaft moves the nut thereon to effect the rocking movement of the adjusting members, and means connected with the shaft facilitating the rota- 'tion of the same.

4. The invention according to claim 3, wherein the last named means comprises a hand wheel, means rotatably supporting the hand wheel on the base remote from said lever, and the means operatively coupling the hand wheel with the shaft comprises a`universal coupling.

No references cited. 

